1. 物质;物品;东西
    A substance is a solid, powder, liquid, or gas with particular properties.

    e.g. There's absolutely no regulation of cigarettes to make sure that they don't include poisonous substances...
           根本没有法规来确保香烟不含有毒物质。
    e.g. The substance that's causing the problem comes from the barley.
           引起该问题的物质来自大麦。

2. 重要性;重大意义
    Substance is the quality of being important or significant.

    e.g. It's questionable whether anything of substance has been achieved...
           是否已经取得了任何实质性进展还是个问题。
    e.g. Syria will attend only if the negotiations deal with issues of substance.
           只有在谈判涉及重大问题时叙利亚才会参加。

3. 主旨;要点;实质;基本内容
    The substance of what someone says or writes is the main thing that they are trying to say.

substance的近义词

    e.g. The substance of his discussions doesn't really matter.
           他讨论的要点实际上根本不重要。

4. 事实基础;根据
    If you say that something has no substance, you mean that it is not true.

    e.g. There is no substance in any of these allegations.
           这些指控都毫无根据。

5. 财力雄厚的;有权有势的；有影响力的
    A person of substance has a lot of money, power, or influence.

    e.g. ...mature men of substance.
           有钱有势的成熟男人